Young Australian backpackers venturing overseas are being warned to rethink volunteering in developing countries as a booming trend of "voluntourism" exposes a darker side of the industry.

Key points:

Volunteer tourism has become a popular option among Australian backpackers

But there are concerns the practice damages children and is open to exploitation

Some tour agents are now pulling back from offering volunteer packages

According to Save the Children Australia, popular voluntourism destinations for Australians such as Bali, Thailand and Cambodia have seen the number of orphanages increase by up to 500 per cent since the trend began.

"Most people mean well, so 'voluntourists' are … choosing holidays or holiday packages and they want an element of doing good in it, and orphanages seem to have been one of the things that attracts people," Save the Children child protection expert Karen Flanagan said.

"Unscrupulous people in developing countries are seeing that opportunity and they're taking children from families or trafficking children, from poor families generally, to meet this demand."

An estimated 80 per cent of children living in orphanages were not orphans and had at least one living parent, according to advocacy organisation ReThink Orphanages.

Ms Flanagan said there needed to be a move away from a residential care approach to children and a focus on returning them to a stable family life.

"Due to the risks to children associated with orphanage tourism and volunteering, government agencies — including DFAT, and major travel, tourism and volunteering codes of ethics and guidelines … — discourage orphanage tourism and unskilled volunteering," she said.

Volunteering left backpacker shocked

It was a situation that shocked Maddi Kent when the Perth backpacker decided to travel to Africa to volunteer at orphanages and schools in 2014 at the age of 19.

"[It was] a big stint for someone that had never left Australia, so it was all a bit daunting," she said.

"I'd lived independently from 16 years old, it took me a while to save the thousands and thousands of dollars that the organisation required for me to go volunteer."

"I was in shock even though I had researched since I was five years old about these cultures and countries," she said.

"I was getting rocks thrown at me, I was getting spat on.

"Working with vulnerable kids, working with kids that have been raped, been tortured, isn't something you hear every day."

The now 25-year-old spent two months in Uganda and four months in Kenya and found there were grave issues with how the volunteering programs in which she was involved were being managed by Western companies.

"The lack of communication is probably first and foremost, but there's also a lack of care," she said.

"If you're not crosschecking the projects that you're sending volunteers to, they could actually be damaging the community or abusing the kids.

"They're not going on the ground and checking is their project sustainable — are there legitimate kids that need help, are they being treated right and are they being fed?"

Travel companies pull back on volunteer packages

In 2015, international travel group Intrepid Travel became one of the first major travel agents to remove all orphanage visits from their advertised trips.

"Intrepid Travel does not offer or support voluntourism, or orphanage tourism for that matter. Children are not tourist attractions, and should not be treated as such," chief purpose officer Leigh Barnes said.

Save the Children's Ms Flanagan said some companies had sought out her charity and others for help in how to offer ethical volunteer tourism holidays.

"Many [companies] when they became aware have absolutely engaged with ReThink Orphanages and Save the Children to say, 'please help us, we had no idea we were actually doing harm, we thought we were doing good'," she said.

University of WA international law expert Melanie O'Brien said travel companies needed to take responsibility for their volunteering programs to avoid supporting unethical practices.

"Companies need to be asking are the money and resources really going to where they are needed," Dr O'Brien said.

"Even if it's two people coming along when I go a few times a year, you know, that's two people not contributing to child trafficking and child exploitation."

Her newly established Evie Grace Foundation now supports multiple projects in Kenya, including providing rescue and rehabilitation support for street children, menstruation education for girls and teaching children about their human rights.

The registered children's charity's latest project is helping to find a new home for the Global Hope Rehab Centre for boys in Kenya.

"I am praying that we have the new land at the start of next year and we will be building the new rehabilitation centre for our boys," she said.

Editor's note August 22, 2019: An earlier version of this story quoted a Save the Children spokesman claiming orphanage numbers had increased up to 6,000 per cent. This figure was supplied in error and has since been corrected to 500 per cent.